The present work deals with preparation of two groups of compounds represented by the general formulae: where R represents one of the following aliphatic groups. and Ar

one ot the lollowing aromatic groups. These compounds have been prepared by dehydrating tributyltin oxide with an organic acid

or by the condensation of tributyltin chloride with an organic sodium salt. It has been found that the reaction proceeded smoothly with yield up to 90% . Some physical constants of these compounds have been also determined. The preliminary biological screening test shows that compounds OTQ02

OT003 and OTQ07 exhibited remarkably high fungicidal effects on hypochnus sasakii shirai.